1. Field of Invention
The present invention relates generally to the field of content-based (e.g., cable, satellite, etc.) distribution networks. In one exemplary aspect, the present invention relates to efficiently managing bandwidth allocation to multimedia programs by utilizing historical bandwidth usage by a user or a group of users.
2. Description of Related Technology
One significant competitive challenge presently faced by operators of content-based networks relates to managing and conserving bandwidth. This includes the reclamation of otherwise under-utilized or unused bandwidth such that the service or customer base can be expanded without significant modifications or build-outs of the underlying network infrastructure. For example, it is desirable to expand the types and availability of “next-generation”network services, including high-definition (HD) broadcast, VOD, high-speed data (HSD), VoIP, Interactive TV, etc. over time, without the need for major capital expenditures or system modifications. Hence, network operators are increasingly focused on techniques for “squeezing” as much capacity out of their existing networks as possible.
In a conventional cable network, bandwidth planning and usage tends to be relatively static over time. A network operator periodically changes the channel line-up to delete channels, add new channels and services or change the relationship between logical channel map and frequency domain location of the channels. Channel line-up changes are done typically few times a year to meet the engineering and business needs and resource available in the network. Thus, channels available in the network stay relatively static when compared to the frequency with which subscribers tune in and out of various program channels.
Typically, a tradeoff must be made between allocating bandwidth to programs currently carried on the network to meet or exceed their quality requirements, yet at the same time keeping sufficient bandwidth in reserve to be made available to new program requests, or sudden changes in available network bandwidth resources (e.g., equipment failure).
With the availability of new technologies such as high definition (HD) programming and streaming technologies to provide users with individualized content, network operators are facing bandwidth “crunch” of sorts, and have started looking at delivery methods on their content networks to optimally utilized bandwidth. One such technology comprises a “switched” network architecture (commonly referred to as switched digital broadcast (SDB), or broadcast switched architecture (BSA)). In such a network, individualized program delivery can be provided to each subscriber.
This new way of offering programming is also changing the conventional ways in which network bandwidth demand changes over a period of time. There is a need for the network operators to meet such fluctuating bandwidth demand by deploying bandwidth allocation strategies that adapt to such changes in bandwidth demand. However, as mentioned before, in conventional content distribution networks, the bandwidth assigned by a cable network operator to the programs distributed over his network is relatively static. The RF spectrum available for transmission over the coaxial part of a cable network is typically divided into 6 MHz channels. A cable operator typically creates a channel lineup by assigning the 6 MHz channels to service tiers such as analog cable, digital cable, video on demand service and data service. For example, the bandwidth available to programs watched by viewers may exceed the actual utilization, in which case the excess bandwidth may be wasted. It is also possible that bandwidth available to programs watched by viewers may fall short of the demand. This may result undesirable effect that additional viewing requests from users may have to be rejected, or bandwidth allocated to programs may have to be reduced, resulting in a loss in the quality of service. Therefore, network operators have begun looking at ways to manage the available bandwidth more intelligently, especially within heterogeneous networks (i.e., those that deliver broadcast, switched broadcast, IP, and session-based delivery such as VOD, as well as services such as DOCSIS).
A number of different technologies for managing or allocating network bandwidth are evidenced in the prior art. For example, U.S. Pat. No. 7,171,687 to Uemura, issued Jan. 30, 2007 entitled “Content Distribution Apparatus” discloses an apparatus acquire contents prior to a distribution request from a client in a time zone having sufficient network bandwidth, and efficiently use network bandwidth. An access trends analysis handler analyzes access to contents by a client, a contents prediction handler predicts contents expected to be in demand in the future based on this analysis result, and a contents acquisition handler acquires the forecast contents in a time zone when there is sufficient network bandwidth. A contents deletion handler predicts contents in the acquired contents for which not much demand is expected from the client contents access trends, and deletes these contents. Due to this invention, a contents distribution apparatus can be provided which enables efficient use of network bandwidth and disk capacity.
United States Patent Application Publication No. 20050202827 to De Marco, et al. published Sep. 15, 2005 entitled “System for predictively and dynamically allocating communication bandwidth” discloses a system that predictively allocates bandwidth within a wireless network in accordance with a mission plan. The system includes a first team member and a second team member. The first team member predicts subsequent communication demand by the second team member in accordance with the mission plan. The second team member predicts subsequent communication demand by the first team member in accordance with the mission plan. The first team member is allocated a bandwidth commensurate with a predicted need of the first team member and a predicted need of the second team member. The second team member being allocated a bandwidth commensurate with a predicted need of the first team member and the second team member.
Unfortunately, the above cited prior art fails to provide a comprehensive solution to the aforementioned issues associated with content distribution networks. Specifically, there is a need for improved methods and apparatus adapted to effectively and (ideally automatically) to manage network bandwidth allocation to overcome problems with the previously discussed static allocation approach. For the ease of deployment in a content distribution network, such improved methods and apparatus should also be one that requires minimal changes to existing infrastructure and also is flexible to allow operator to change operational parameters to adapt the technique to run-time changes in the network bandwidth utilization.
It would also be ideal to provide methods and apparatus that allow the network operator to exceed program quality or bitrate requirements (in terms of bandwidth), yet at the same time avoid having to keep undue amounts of bandwidth in reserve to make it available to new program requests or sudden changes in available network resources.